In solving geological and archaeological questions we apply Optically Stimulated Luminescence (OSL) dating to a wide range of depositional environments including lake, river, aeolian, glacial and peri-glacial environments as well as cave-mouth sediments and other more exotic deposits.

OSL dating allows the age of sedimentary deposits to be accurately constrained and has revolutionized studies of events that occurred in the past ca. 300 000 years of Earth´s and humanity´s history. OSL dating is based on the principle that mineral grains, such as quartz and feldspar, absorb energy that originates from naturally occurring ionizing radiation in the sedimentary environment. The radiative energy is stored in the crystal lattices of these minerals in the form of trapped electrons and the number of trapped electrons increases over time. Optical read out of these electrons under controlled laboratory conditions thus provides a tool to constrain the depositional age of sediment.

More recently OSL has also been used as a chronometer for dating geological and archaeological rock surfaces. This approach exploits the fact that the latent OSL signal in the topmost centimeters of rock surfaces is gradually reduced while exposed to sun light. We pioneer OSL rock surface dating and apply it to alpine rock slope failures and archaeological surface artefacts and petroforms.

Current projects

This project investigates the climate, landscape and archaeological history of the upper Tibetan Plateau between 50 and 11 ka, the period when Homo sapiens first ventured into oxygen-depleted centre of High Asia.

The project will use existing and recently developed OSL methods in novel ways in order to date the use of lithic quarries, the construction of stone arrangements and the accumulation of surface artefact scatters.

We use single-grain OSL techniques to construct an accurate OSL chronology for the cave-mouth sediments at Vindija Cave, a key site for the study of the Middle and the early Upper Palaeolithic of Europe.